Improvement in lathes



5min/5 @anni wweeee- @film Letters Patent No. 91,910, dated June29,1869.

IMPROVEMENT 1N LATHES.

The Schedule referred to in these Letters Patent and making part of thesame.

To all whom it may conce/rn Be it known-that I, CHARLES S. CLARK, ofProvidence, in the county of Providence, and State of Rhode Island, haveinvented an Improvement in Engine- Lathes; and do hereby declare thatthe following is a full and exact description, reference being had tothe accompanying drawings, making a part of this specifi cation. Y

To enable those skilled in the art to make and use my invention, I willproceed to describe its construction and operation.

In Figure 1 A is the poppet-block.

B, the tool-rest. Y

O C are two wedges, dovetailed into grooves in the poppet-block andtool-rest, as .shown in Figure 2.

D is a screw, furnished with right and left-handed threadsin order tooperate the two wedges simultaneously.

E is a pin, which operates to hold the tool-rest in a central positionto the action of the two wedges.

As the screw is turned, the wedgeswill be thrown together, or drawnapart, thus elevating or depressing the tool-rest, as desired. v v

Instead ot' using a right and left-hand screw, a single screw may beused, acting in one of the wedges, the other wedge being retained bycollars iu afixed position with regard to such screw.v

Figure 4 shows the arrangement where only one wedge is used, the samebeing secured to the poppetblock and tool-rest by means ot' the screws Eand F' operating in the slots G and G'.

As the wedge is drawn in or out by the action of the screw, thetool-rest will be elevated or depressed, as desired..

The pin E, passing from the tool-rest to a hole in the poppet-block,holds the rest in position againstthe action of the wedge.

' In case it is desired to hinge the tool-rest to the poppet-block, asshown in Figure 3, a wedge, having a joint between vits two faces,should be used, such wedge being readily adapted to the varyinginclination of the' tool-rest, as 'the saine is bein-g raised orlowered.

The wedges, instead of 1being operated by means of a screw, as shown,may be operated by cams, or their equivalents.

What I claim as my invention, and desire to secure by Letters Patent,is-

The combination ofthe poppet-block A, tool-rest' B, wedges O C, andscrew D, or their equivalents, as set forth, all constructed, arranged,and fitted together substantially in the manner described.

, CHARLES S. CLARK.

Witnesses:

HENRY MARTIN, CHARLES SELDEN.

